- Libro electrónicoOn the Age of Maya RuinsCharles P. Bowditch
- Libro electrónicoOn the Age of Maya RuinsCharles P. Bowditch
- Libro electrónicoWas the Beginning Day of the Maya Month Numbered Zero (or Twenty) or One?Charles P. Bowditch
- Libro electrónicoMemoranda on the Maya Calendars Used in the Books of Chilan BalamCharles P. Bowditch